Help needed trying to interpret neutral to Ground Voltage readings?

[gdhm]

Sorry about the above incomplete post. It posted itself whilst I was typing and I do not know what I did wrong I then edited it, but when I went to post the completed version the "edit" option had timed out.. so here is the full post. (EDIT I've removed it, Crossy)

Crossy,

I am running around like a Headless chicken (make that ignorant headless chicken).

I tried to check out Sneider 63A RCBOs in Khon Kaen HomePro and Home hub but ran into a brick wall. Items in HomewPro that looked like they MAY be the correct items did not say RCBO on the price tags. Then again the price tabs of itesm seemed to be rasnginh between almost ฿2000 to ฿3000+. Home Hub did nto have any in stock and only seemd to sell 32A. Do you know the model codes of the 63A Sneider D RCBOs?

Secondly IF these items are really well over ฿2,000 each and I need 2 then I wonder if the separater Safe-T-Cut boxes (whenr eyou can select sensitivity as well) are not better value.

Having decided that I may well have understimated tyhe price of the in CU RCBOs I looked at the separate boxes. I found Safe-T-Cut Gold units but they maxed out at 63A per unit as did Safe-T-Cut units. (who seem a different company to Safe-T-Cut Gold (how confusing).

The English side of Safe-T-Cut is not working so and the Safe-T-Cut Gold ar eonly in Thai anyway. ONLY Safe-T-cUT seem to have any unit rated at 100A and the only price reference I could find anywhere on the web wiht a retailer was around ฿17000

Crossy,

I am running around like a Headless chicken (make that ignorant headless chicken). I thought go to Homepro, Homebub maybe Global and make a decision but came out totally confused.

Today I tried to check out Schneider 63A RCBOs in Khon Kaen;s HomePro and Home hub but ran into a brick wall. Items in HomePro that looked like they MAY be the correct items did not say RCBO on the price tags so could not tell. The prices of these items seemed to be high (to me) ranging between almost ฿2000 to ฿3000+. Home Hub did not have any in stock and only seemed to sell 32A when they do have stock.

1) Do you know the model codes of the 63A Sneider-D series RCBOs?

and are they expensive?

2) IF these Schneider RCBO items really are well over ฿2,000 each and as I need 2 then I wonder if the separate "Safe-T-Cut" type boxes (where you can select sensitivity as well) are not better value. What do you think?

3) Having decided that I may well have underestimated the price of the "in-CU" Schneidier RCBOs I looked at the separate boxes. I found "Safe-T-Cut Gold" units but they maxed out at 63A per unit, as did the "Safe-T-Cut" units (seem to be two different companies -how confusing).

The English side of "Safe-T-Cut's Website is not working at all, and the Safe-T-Cut Gold's website is only in Thai anyway. ONLY Safe-T-CUT seem to have ONE unit rated at 100A and the only price reference I could find anywhere on the web was around ฿17000+ AND I am unsure it the these units are 3 pole or 2 pole and some sites refer to the Special A as 3 pole. Certainly seems a colossal price jump form 63A units.

I really need to ask your expertise on a possible solution I am wondering about, if you are willing to advise further Crossy.

1) Assuming the Schneider's ARE very expensive as I suspect they are and I'd need 2 (I was also concerned that some posters in the past on this site questioned their reliability)

AND

2) Assuming I may well not be able to track down a 100A separate "Safe-T-Cut" type separate unit (or one that is not a silly price) is it a realistic, feasible and safe proposition to think about 2 separate "Safe-T-Cut 63A" type units with the N-L feed cables from the street meter being split to feed each Unit and then each unit feeding its respective 63A Schneider D series CU ( I have 2).

Can one safely split live cable into two live and Neutral into 2 cables?

Would balance be OK?

Would there be unexpected (for me) consequences if I wished to do that type of installation?

IF you answers are yes it is safe, acceptable and a feasible solution with no negatives then what type of splitter would be appropriate for thick 30A cables coming off my 30/100A meter?

I know an RCBO is regarded by you and all on this site as essential, but I worry I can do this if I have to rely on the BS I am being fed by Sales Assistants and local Electricians here who clearly do not know their onions enough (or at all) for me to trust what they say. I do not want to jump out of the frying pan into the fire and make my system less safe than it is now due to my ignorance on the issues and fitting.

I take electrocution seriously as I am ashamed to say I have electrocuted myself 4 times during my life time, 2 UK 1 in Spain I once here (1 as a child finger up live empty wall light socket with bulb - that was the worst, and 3 times extension lead type STUPID errors whilst wring/fitting. Apart from a sharp gnawing type sensation up my fingers and hand and slightly into lower arm (higher when a child) I never suffered further and was always able to let go). In my ignorance I have always felt this type of accident as highly unpleasant but unlikely to be really serious until reading this site and mistakenly I never felt I was maybe lucky it was not much worse or fatal. Maybe being obese much of my life helped (no idea).

Anyway Crossy, I AM serious about a RCBO solution to my system but am really struggling on which way to go and exactly what I need. Your advice goes a "HELL OF A LONG WAY" in making sure I am do not risk believing potentially dangerous BS by retailers and local so called "electricians".

Regards

Dave

Edited June 27, 2013 by Crossy

[Crossy]

No problem Dave, let's get you sorted.

This answer will come in several parts as I'll need to do some checking, this is part 1

A dead give-away in determining if a device offers earth leakage protection (i.e. is an RCD or RCBO) is the presence of a 'Test' button, no button = regular breaker.

More to come later.

[Crossy]

Part 2

The Schneider / Square-D device you need is QO263MBGX30 - 2 pole 63A/30mA plug-in RCBO Thai Interelectric have these catalogued at 4,800 Baht Ouch!

Not sure how current this catalogue is mind http://www.thai-interelectric.com/images/1130920959/new_schneider_residential.pdf (Page 18)

This is the easiest solution as you simply replace the incoming 63A breakers with these devices.

I think I can come up with a cheaper method, but first please can you post close up photos of the two consumer units, left hand ends, ensure you include the ground and neutral bars in the images, I need to see how the incoming cables are routed.

EDIT I think the earlier photos are good enough.

If you can get the part numbers of the existing incoming breakers that will help ensure that we source the correct RCBOs, You'll likely have to order them from your local electrical shop rather than Homeworks

EDIT 2 Can you also check that turning off either of the main breakers does not affect the other consumer unit?

[Crossy]

Part 3 the cheaper solution. Assumes that the two consumer units do not affect one another, see post above.

• Go to your local electrical emporium and source two DIN mount 63A/30mA RCDs (note that since we are retaining the existing incoming breakers we don't need RCBOs - cost saving 1). Examples of suitable devices would be: ABB FH202-63 or BTICINO 008911 (much cheaper than the ABB unit) both are available in HomePro.
• Whilst you're there pick up a couple of the small plastic boxes intended for mounting these DIN breakers, they're about 100 Baht or so and have a plastic DIN rail moulded in so the RCD simply clips on.
• Get a couple of metres of 16mm² single cable type THW http://www.bangkokcable.com/catalog/BCC_CATALOG/THWEN.HTML
• Go home.
• Do you have a pet sparks? If so go and find him as you're going to need to isolate your supply at the meter, no way anyone would do the next bit live with a metal CU.
• With the supply confirmed off, note the two leftmost knockout plates on the bottom of your CUs - knock them out. These metal knockouts can be a bit of a wrestle. You may want to clean up any sharp edges of the holes with a file.
• Remove the Live incoming cable from the breaker and feed it through the left knockout. Mark it with some tape so you don't confuse the wires.
• Do the same with the Neutral, again feeding it through the left hole.
• Fix your nifty plastic box complete with RCD to the wall below the CU, don't make it too close or you'll struggle to bend the wires.
• Connect the dangling wires into the top of the RCD, convention says Live goes on the right.
• Cut a length of the 16mm2 THW to run from the bottom of the RCD, back up to the incoming breaker through the right hand hole.
• Connect it to the Live side of the breaker and the live output of the RCD (bottom right terminal if you put the live supply top right)
• Repeat for the neutral side.
• Trim the plastic cover to fit over your new cables.
• Repeat 6-14 with the other CU.
• Check everything.
• Check everything again. If you have a meter ensure there is no short between L and N (it should be very difficult to get this wrong anyway)
• With your new RCDs in the off position reconnect your power.
• Turn on the RCDs, hopefully they will remain on and you're good to go.

Of course, you could do this with two 63A Safe-T-Cut units, adjustable and already in nice boxes too but not so cheap.

It looks like your incoming supply is already split to feed the two CUs, I'll bet it's twisted and taped somewhere behind that panel The correct way to split the supply would be to use a Henley Block:

Good luck finding in Thailand, mine came from the UK.

[doglover]

^^^^ Good suggestion and step by step to implement.

Probably end up costing the OP about 1000 baht per CU as opposed to his quoted 4000 baht for a respectable brand. I'm surprised the OP is stalling at the cost as he must have forked out a pretty baht for his dual Schneider CU's already anyway.

Cheap RCD protection is the route I recently took with a rental house. But it would be good to hear comment from one of the engineers if buying a cheap RCD is really worth it?

[IMHO]

Part 2

The Schneider / Square-D device you need is QO263MBGX30 - 2 pole 63A/30mA plug-in RCBO Thai Interelectric have these catalogued at 4,800 Baht Ouch!

Not sure how current this catalogue is mind http://www.thai-interelectric.com/images/1130920959/new_schneider_residential.pdf (Page 18)

This is the easiest solution as you simply replace the incoming 63A breakers with these devices.

I think I can come up with a cheaper method, but first please can you post close up photos of the two consumer units, left hand ends, ensure you include the ground and neutral bars in the images, I need to see how the incoming cables are routed.

EDIT I think the earlier photos are good enough.

If you can get the part numbers of the existing incoming breakers that will help ensure that we source the correct RCBOs, You'll likely have to order them from your local electrical shop rather than Homeworks

EDIT 2 Can you also check that turning off either of the main breakers does not affect the other consumer unit?

The latest house I built also has dual 14 breaker Square-D load centers, and dual 63A Schneide RCBO's and that price sounds about right...

Have to agree with doglover here - why use the best up to now, and then go cheap on your protection? Makes no sense to me.

[Crossy]

No argument from me, it's the simplest and most elegant solution.

OP was looking to lower the cost.

[gdhm]

Hi Crossy and all,

Terrific info Crossy I am embarrassed it must have taken you a long time.

I know nobody here is criticizing my cost concerns but as you all have been wonderful in your advice to me I want (for info not griping) to explain my fears on costs.

What Cost means in my circumstances. When I came here 7 years ago my current UK private pension would have been worth about ฿78,000 (with 7 years less RPI). Now due to erosion of the UK exchange rate to Baht (69 down to 47 Baht to 1GBP) it is ฿53,500 and there has been 7 years of Thai RPI.

I am 61 and 160 Kilos so of course even if I could afford Health insurance I cannot get it (and there would be exclusions if I could) so I am 100% exposed that if I become ill I will have to use Khon Kaen General Hospital and pay whatever prices they decide to hit a Farang with. The wonderful UK has all but stabbed UK Expats living outside EU in the back. Frozen the lousy State pensions (for life) and if I need free healthcare in UK I would have to move there and survive for 6 months before I could get what I contributed to for all my working life since 17 years old. 375,000 Baht is tied up in a savings account to support my Retirement Visa. If I wanted to or had to live in UK neither my wife nor my stepson would be allowed to come with me, because under new UK rules my income is so low (and well inside in the poverty zone) my wife would not qualify to live with me in the UK, even if I had no stepson son as my earnings are not sufficient for her to apply (So MUCH for UK human rights) .

Essentially Thailand has no responsibilities to me (FAIR ENOUGH) and my home Nation UK have disowned me and all their none EU Expats in every way they can, whilst still taking UK income tax from my UK pension (as they do with all UK pensions (private or not).

THIS IS REALITY for me and all non EU Expats. Those who are well off need not worry but the rest of us may (like me) have a lot to worry about. I gifted the purchase price of and to my wife and built us all a home and bought a Toyota Pickup. My reserves are effectively zero having invested in my family - a choice I will never regret as these last 7 years have been the happiest of my life.

Anyway, bottom line there is NO question that RCBOs ARE worth the protection even if ฿4000 baht each.

Reality is however I have to make "lesser of evils" decisions. I AM likely to need hospital care as I age unless at my weight a heart attack takes me clean out (probably best for me and family as I do not wish my family to have no house, car etc coz the hospital needed paying). My wife will receive currently 30,000 Baht pm for life max 5% UK rpi increases each year (whether she marries or not from my private pension (nothing from the wonderul UK state pension - one of the worst in Western Europe).

Hence why I baulk on ฿8,000 for 2 Schneider RCBOs that cannot even be adjusted for sensitivity whereas two Safe-T-Cut units would cost less or almost the same. (Added to that my house is only 7 years old wiring mostly earthed and a high probability no one would be seriously electrocuted. The shower and water units all have working ELCBs).

Crossy I really appreciate your detailed cheapest option but I am not confident enough to do such a procedure even though your instructions are clear and detailed I just do not like messing with electricity unless I 100% know what I am doing. If i screwed up I may put other more in danger than if I had not done anything.

Based on your other info however, I think you have confirmed that PROVIDED the 2 CUs are fed separately (THEY ARE as power does not go off in every circuit when one of other box is switched off). I know all 3 shower heaters, 2 water heaters, air-cons and oven are all fed from one CU - must push its 63A on rare occasions as one water heater is 5Kw. Power outlets seem to be fed from the other. I have not worked through all the fuses yet but as and when I need to identify or become aware I label the CU breakers accordingly).

So my intention will be to get 2 "Safe-T-Cut" type 63A RCBOs units. One for each CU and then I can trial and error the highest sensitivity each can be set to without nuisance tripping.

Your comment: It looks like your incoming supply is already split to feed the two CUs, I'll bet it's twisted and taped somewhere behind that panel The correct way to split the supply would be to use a Henley Block:

Good luck finding in Thailand, mine came from the UK.

So what do Thais do Crossy?

I do not know how my house builder electrician split the cables from the meter to each of the CUs.

I will try to track down Henley Block and casing.

If the Safe_T_cuts have a large enough L and N screw connector, could I send Live and neutral to one Safe-T-Cut and with the same gauge cable daisy chain the Live and Neutral from one unit's L and N inlets inlet to the other's L and N inlets?

If so it that safe or would it have unwanted affects on either unit?

Thanks ever so much Crossy and all

Dave

Edited June 28, 2013 by gdhm

[IMHO]

Hi Crossy and all,

Terrific info Crossy I am embarrassed it must have taken you a long time.

I know nobody here is criticizing my cost concerns but as you all have been wonderful in your advice to me I want (for info not griping) to explain my fears on costs.

What Cost means in my circumstances. When I came here 7 years ago my current UK private pension would have been worth about ฿78,000 (with 7 years less RPI). Now due to erosion of the UK exchange rate to Baht (69 down to 47 Baht to 1GBP) it is ฿53,500 and there has been 7 years of Thai RPI.

I am 61 and 160 Kilos so of course even if I could afford Health insurance I cannot get it (and there would be exclusions if I could) so I am 100% exposed that if I become ill I will have to use Khon Kaen General Hospital and pay whatever prices they decide to hit a Farang with. The wonderful UK has all but stabbed UK Expats living outside EU in the back. Frozen the lousy State pensions (for life) and if I need free healthcare in UK I would have to move there and survive for 6 months before I could get what I contributed to for all my working life since 17 years old. 375,000 Baht is tied up in a savings account to support my Retirement Visa. If I wanted to or had to live in UK neither my wife nor my stepson would be allowed to come with me, because under new UK rules my income is so low (and well inside in the poverty zone) my wife would not qualify to live with me in the UK, even if I had no stepson son as my earnings are not sufficient for her to apply (So MUCH for UK human rights) .

Essentially Thailand has no responsibilities to me (FAIR ENOUGH) and my home Nation UK have disowned me and all their none EU Expats in every way they can, whilst still taking UK income tax from my UK pension (as they do with all UK pensions (private or not).

THIS IS REALITY for me and all non EU Expats. Those who are well off need not worry but the rest of us may (like me) have a lot to worry about. I gifted the purchase price of and to my wife and built us all a home and bought a Toyota Pickup. My reserves are effectively zero having invested in my family - a choice I will never regret as these last 7 years have been the happiest of my life.

Anyway, bottom line there is NO question that RCBOs ARE worth the protection even if ฿4000 baht each.

Reality is however I have to make "lesser of evils" decisions. I AM likely to need hospital care as I age unless at my weight a heart attack takes me clean out (probably best for me and family as I do not wish my family to have no house, car etc coz the hospital needed paying). My wife will receive currently 30,000 Baht pm for life max 5% UK rpi increases each year (whether she marries or not from my private pension (nothing from the wonderul UK state pension - one of the worst in Western Europe).

Hence why I baulk on ฿8,000 for 2 Schneider RCBOs that cannot even be adjusted for sensitivity whereas two Safe-T-Cut units would cost less or almost the same. (Added to that my house is only 7 years old wiring mostly earthed and a high probability no one would be seriously electrocuted. The shower and water units all have working ELCBs).

Crossy I really appreciate your detailed cheapest option but I am not confident enough to do such a procedure even though your instructions are clear and detailed I just do not like messing with electricity unless I 100% know what I am doing. If i screwed up I may put other more in danger than if I had not done anything.

Based on your other info however, I think you have confirmed that PROVIDED the 2 CUs are fed separately (THEY ARE as power does not go off in every circuit when one of other box is switched off). I know all 3 shower heaters, 2 water heaters, air-cons and oven are all fed from one CU - must push its 63A on rare occasions as one water heater is 5Kw. Power outlets seem to be fed from the other. I have not worked through all the fuses yet but as and when I need to identify or become aware I label the CU breakers accordingly).

So my intention will be to get 2 "Safe-T-Cut" type 63A RCBOs units. One for each CU and then I can trial and error the highest sensitivity each can be set to without nuisance tripping.

Your comment: It looks like your incoming supply is already split to feed the two CUs, I'll bet it's twisted and taped somewhere behind that panel The correct way to split the supply would be to use a Henley Block:

Good luck finding in Thailand, mine came from the UK.

So what do Thais do Crossy?

I do not know how my house builder electrician split the cables from the meter to each of the CUs.

I will try to track down Henley Block and casing.

If the Safe_T_cuts have a large enough L and N screw connector, could I send Live and neutral to one Safe-T-Cut and with the same gauge cable daisy chain the Live and Neutral from one unit's L and N inlets inlet to the other's L and N inlets?

If so it that safe or would it have unwanted affects on either unit?

Thanks ever so much Crossy and all

Dave

Plenty of "henley block" style buss-bars available in TH.

[IMHO]

No argument from me, it's the simplest and most elegant solution.

OP was looking to lower the cost.

Yeah I get that, to me it's like putting Deestone tires on a Benz though

[gdhm]

Plenty of "henley block" style buss-bars available in TH.

That's great news.

Looks like I have my solution. 2 "Safe-T-Cut" type RCBOs Henley Block type unit. Not as cheap (by far) as Crossy's alternative solution BUT I appreciate Crossy bothering to offer various acceptable solutions and for a low cost being included for my consideration. Cannot hope or ask for more!.

This D.I.Y forum has for me (a life insurance white collar worker all my working life) been great since I had my house built. So many knowledgeable and kind people bothering to help me and others who really need help and guidance in a country where so often language is a major risk factor for misunderstandings inability to get real solutions.,Regretfully where so many local "experts know how to build, plumb and wire and where even the genuinely more knowledgeable tend to do things the "way they have always done them ... for the last 30- 40 years.

A helpful Forum like this really does help "sort the wood from the trees" and from kindly people with no vested interests other than help those in need of good advice.

Thanks ever so much Crossy. IMHO, Steve, Lancelot and Doglover

Dave

Edited June 29, 2013 by gdhm